Frailea - The Cleistogamous Cactus

Cleistogamous - Botany. Of or relating to a flower that does not open and is self-pollinated in the bud.

Frailea pumila is a small cactus from the grasslands of Argentina, Uruguay, and Paraguay.  For most of its life it stays pretty much hidden in the grass, but every now and then it comes forth with a halo of bright yellow flowers, attracting any pollinators in the vicinity.  

Unlike most cacti, fraileas don't really have to flower to produce fruit and seed.  They are part of an unusual group of plants that have cleistogamous flowers.  For me it is rare and exciting to see fraileas. They usually produce little round, dry fruits without flowering.  This past Sunday, when F. pumila unexpectedly produce its lovely yellow flowers, it became an instant blog item. 

The genus Frailea was named in honor of Manuel Fraile, who years ago, maintained the cactus collection of the U.S. Department of Agriculture in Washington, D.C., which by the way, is the city in which I was born.